<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            list-style: none;
        }
    </style>
</head>

<body>
    <div id="app">
        <input v-model="val" type="text">
        <button @click="addItem">添加</button>
        <div>
            <h2>
                正在进行 --- {{ len }}
            </h2>
            <ul>
                <li v-for="(item, index) in arr" v-show="!item.checked">
                    <input v-model="item.checked" type="checkbox"> {{ item.val }}
                    <button @click="s(index)">删除</button>
                </li>
            </ul>

            <h2>
                已经完成 --- {{ arr.length - len }}
            </h2>
            <ul>
                <li v-for="(item, index) in arr" v-show="item.checked">
                    <input v-model="item.checked" type="checkbox"> {{ item.val }}
                    <button>删除</button>
                </li>
            </ul>
        </div>
    </div>

    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <script>
        new Vue({
            el: "#app",
            data: {
                val: "",
                arr: []
            },
            created() {

            },
            computed: {
                len() {
                    return this.arr.filter((item) => {
                        return item.checked === false
                    }).length
                }
            },
            methods: {
                addItem() {
                    this.arr.push({
                        val: this.val,
                        checked: false
                    })
                    this.val = ""
                },
                s(index) {
                    this.arr.splice(index, 1);
                }
            }
        })
    </script>
</body>

</html>